1. Field of Invention
An improved base structure for a lower mast of a pivotal drilling rig structure provides at least two A-frame support members affixed to the rig side of the lower mast, the drilling rig structure being elevated to a point slightly forward from vertical position towards the well side, with the A-frame support members held in a drilling position by respective support member struts which apply force against the A-frame support members during use of the drilling rig structure to enhance the drilling forces applied during the drilling process. A rig side secondary locking support structure secured to an elevating drilling rig platform provides additional stability to the drilling rig structure when the drilling rig is in an operational position subsequent to the positioning of the A-frame support members and the support member struts.
2. Description of Prior Art
A preliminary review of prior art patents was conducted by the applicant which reveal prior art patents in a similar field or having similar use. However, the prior art inventions do not disclose the same or similar elements as the present improved derrick and associated apparatus, nor do they present the material components in a manner contemplated or anticipated in the prior art.
In U.S. Patent Application No. 2009/0272540 to Rodgers, a mobile hydraulic work-over rig is disclosed, which includes a rig having a derrick elevated on a base structure comprising containers for equipment used in association with the drilling or work-over activity, a work platform including pipe rack sections for storing pipe, with the derrick being open sided with a power cylinder at an upper end for lifting and lowering pipe section away from and into each well, and hydraulic drive cylinders for advancing the rig between wells without telescoping or pivoting the derrick into a travel position, all of the hydraulic components being operated from a central control panel on the work platform.
Telescoping derricks on workover rigs are disclosed in U.S. Pat. No. 7,461,831 to Mosley, U.S. Pat. No. 5,450,695 to Desai, U.S. Pat. No. 4,932,175 to Donnally, U.S. Pat. No. 4,590,720 to Reed, and in U.S. Pat. No. 4,969,776 to Bunce. More specifically, Bunce discloses an offshore rig with has extendable caissons with a topside platform, the caissons extending to the bottom of the sea floor, providing a stable working platform. Reed has a plurality of element which telescope one into another so that the derrick can be raised from a short collapsed position into an extended position by the use of four cables, one in each corner of the derrick. Donnally is a telescoping derrick that is light for easy transport and uses structure to enable the mast to be raised from a collapsed horizontal position to a vertical position by hydraulic cylinders, the mast in an retracted position and later the being telescopically raised to full height by a cable means. Mosley is relatively similar to Donnally and also the Rodgers assembly. A very established collapsible derrick tower, using a cable hoist, is disclosed in U.S. Pat. No. 1,299,261 to Taylor.
In U.S. Pat. No. 5,161,639 to Ice, a telescoping rig is disclosed having a safety line attached to the crown which is used to secure a worker within a harness while climbing up the derrick tower. This harness device includes a counterweight within a telescoping tube. This derrick, which is not indicated on a portable rig also appears to have two lower support fins although no function is noted for these lower fins.
Other patents indicate features in prior art which are hereby disclosed and improved in the present derrick and apparatus, including U.S. Pat. No. 5,697,457 to Back, which provides a drilling derrick or mast transported on a trailer of a vehicle, which is raised into a vertical position using a pivotal means and a hydraulic ram to elevate the derrick or mast from a horizontal transport position tot a vertical drilling position. In U.S. Pat. No. 4,757,592 to Reed, a method is disclosed which provides a jacking crane erecting four telescoping hydraulically powered legs used to erect a “two spaced parallel column drilling derrick.” This is built upon a mud sled platform which provides a secure stable platform upon which to build the drilling derrick.
A telescoping drilling rig is indicated in U.S. Pat. No. 4,932,175 to Donnally which involves a substructure pivotally connecting a lower mast section which is raised and lowered between a horizontal position and a vertical position by a power means (cable), FIG. 5, and an upper mast section being in sliding engagement with the lower mast section, FIGS. 6-7, and a guide assembly for connection between the upper and lower mast sections with foot for securing the upper mast section for telescoping movement within the guide assembly as indicated in FIGS. 2 and 4.
A variety of different A-frame structures utilized in the base of a drilling rig are demonstrated in several patents, including U.S. Pat. No. 5,794,723 to Caneer, Jr., U.S. Pat. No. 4,465,144 to Gugger, U.S. Pat. No. 4,447,997 to Delgado and U.S. Pat. No. 4,024,924 to Houck. In Houck, the A-frame is a stationary stop attaching to a table structure, which is used to buttress a standing vertical derrick. A quite similar situation is disclosed in the Delgado patent, where the A-frame is erected and affixed to the floor of the drilling rig and a vertical cable is used to raise the derrick from a horizontal position into a vertical position, with the A-frame providing a locking attachment for the derrick to maintain the vertical position. In Gugger, an A-frame structure is mounted to the rear of the derrick trailer, with the upper end of the A-frame being pivotally attached to the derrick while a piston ram elevates the derrick from a horizontal transport position to a vertical drilling position, with the derrick further held into position by a plurality of wedges or locking pins at the upper end of the A-frame and the lower end of the A-frame. A somewhat similar inclusion of an A-frame support component is used in the Caneer, Jr., apparatus.
Use of a top drive drilling component on a vertical drilling rig is demonstrated in several drilling rig patents, including U.S. Pat. No. 7,828,086 to Lesko, U.S. Pat. No. 7,290,621 to Orr, U.S. Pat. No. 6,913,096 to Nielsen, U.S. Pat. No. 6,412,576 to Meiners U.S. Pat. No. 6,336,622 to Eilertsen U.S. Pat. No. 6,112,834 to Barrett, U.S. Pat. No. 4,753,300 to Shaw, and U.S. Pat. No. 4,478,291 to Futros, with these top drive mechanisms developed for practical use in the oil fields in the 1980's, even though conceived as early as the 1920's, to overcome the limitations of rotary table drilling systems. These top drive systems provided a means of drilling an entire stand of drill pipe, or multiple single strands of pipe connected together, where the rotary table drilling only provided for the drilling of a single pipe strand at one time. over time, these top drive assemblies have also provided the ability to deliver drilling mud and chemicals to the drilling stem. These top drive assemblies have had difficulty with handling the connection and disconnection of drill pipe, but the moving and handling of stands of drill pipe. Another problem with top drive assemblies is that they do not efficiently provide stability against great rotational force torques sometimes applied to them while being used with a hydraulic drilling system, the higher torque being used for deeper wells or for directional horizontal drilling. The advance of the top drive apparatus is disclosed by the top drive system employed in the present invention.
Thus, as seen in the prior art, Futros discloses a top drive connected to a chain which uses a pulley system to divert the pressure of lifting the top drive and applying drilling pressure to the base of a drilling derrick instead of the drilling pressure being forced against the top of the derrick. Eilertson indicated the use of a lifting device having rack segments which are moved up and down by using driving gear and shifting the load handles by the lifting tackle to the bottom of the derrick.
A double derrick drilling rig is disclosed in the Meiners patent which provides a top drive with two opposing guide trolleys on the ends of opposing counter-torque arms which are directed against some object on each of the two derrick towers, and presumably some type of tract, since the guide trolleys appear to have some type of four wheeled rolling means on each guide trolley. More directly, a top drive integrating within a drilling rig is the subject of the Orr patent, wherein the derrick is provided with a track system on the inner surfaces of the derrick, which may be a telescoping derrick assembly, with the top drive having a plurality of pads engaging a pair of structural guide rails comprised of a pair of rectangular tubes which extend the length of the mast of the derrick assembly. The top drive is suspended from the crown by a wire being guided over pulleys to raise and lower the top drive along the length of the mast or derrick. The top drive is locked in position along the mast by lock pins during maintenance or transport. The pads on the top drive are part of a disclosed vertical “guidance and torque reaction mechanism”.
Most recently, Lesko discloses a guide rail system for a telescoping mast on a drilling rig which disclose a rail system on the inner portion of the telescoping mast having parallel guide tracks of tubular steel welded to the derrick, with the lower and upper mast sections each having these guide tracks, FIG. 8. The top drive provides an upper and lower set of track wheels facing opposing outer directions from the top drive, each wheel defining a hub, an inner ridge, a middle ridge and an outer ridge, the ridges positioned on the outer margins of the guide tracks, FIG. 9. This three ridge track wheels allow for a transition between the guide tracks of the lower mast when transferring position to the upper mast.